A roller for use in a developing unit of an image forming apparatus may include a non-conductive shaft member and a non-conductive member to surround at least a part of an outer periphery of the shaft member. The shaft member may include a cylindrical rolling part and a pair of support parts formed to project from both ends of the rolling part in a lengthwise direction. The rolling part of the shaft member may be arranged opposite a charge roller in a developing unit and may rotate in contact with the charge roller to absorb and remove foreign substances adhered to a surface of the charge roller.